As the production process of an aminomethyl group-containing benzamide compound, several processes are known. Examples of the production process of 4-aminomethylbenzamide include a process of suspending 4-cyanobenzamide in ammonia-containing methanol and reacting the suspension at room temperature using Rh/Al2O3 as a catalyst (Unexamined Japanese Patent Publication (Kokai) No. 60-139670), a process for contact hydrogenation of 4-cyanobenzamide in the presence of ammonia using a sponge nickel catalyst (Unexamined Japanese Patent Publication (Kohyo) No. 8-505862) and a process of treating a hydrochloride of 4-aminomethylbenzoate ester with ammonia (U.S. Pat. No. 3,817,981).
The process using 4-cyanobenzamide as a starting material exhibits poor productivity because the reaction is conducted at low concentration and low yield. Also the process using 4-aminomethylbenzoate ester as a starting material does not exhibit good productivity because it requires a multi-stage reaction and a complicated operation in order to obtain the starting material.
An object of the present invention is to produce an aminomethyl group-containing benzamide compound with high purity, which is useful as intermediates for medicaments and pesticides, represented by the general formula (II):
wherein —CONH2 and —X represent a substituent on the benzene ring and exist at the meta- or para-position of —CONH2—CH2NH2, X represents a chlorine atom or a fluorine atom, and n represents an integer of 0 to 4, provided that, when n is 2 or more, X may be the same or different, with high yield using an industrially useful process.
The present inventors have found that the above object can be achieved by converting a cyano group (—CN) on the benzene ring into an amide group (—CONH2) using, as a starting material, an aminomethyl group-containing benzonitrile compound represented by the general formula (I):
wherein —CN and —X represent a substituent on the benzene ring and —CN exists at the meta- or para-position of —CH2NH2, X represents a chlorine atom or a fluorine atom, and n represents an integer of 0 to 4, provided that, when n is 2 or more, X may be the same or different, and thus the present invention has been completed.